The present invention relates to a new and improved method of stacking printed products which continuously arrive in a substantially imbricated or fish scale overlapping arrangement, and furthermore, pertains to a new and improved construction of apparatus for the performance of the aforesaid method as well as to a stack produced in accordance with such method and the use of such method.
In the context of this disclosure the expression "fish scale" arrangement or "fish scale" overlapping arrangement of products or articles is intended to mean an arrangement of substantially flat structures which are disposed in an overlying spread formation, in other words, in the manner of a fanned deck of cards.
With conventional stacking techniques of the aforementioned general type, the fish scale product stream is eliminated and transformed essentially into a stack of quadratic configuration wherein the printed products practically completely mutually cover one another in superimposed formation.
It should be relatively self-evident that such essentially quadratic-shaped stack, with the present day output of rotary printing presses, grows quite rapidly in height, this being particularly the case when handling thick printed products, for instance, voluminous newspapers or the like. On the other hand, it should be equally apparent that a conventional stack cannot be built-up to any random desired height. Also, it is to be appreciated that is an essential requirement with respect to rationalization of the processing operations that the printed products which arrive in the fish scale arrangement should be brought into a configuration or formation which in its entirety can be stored, transported and handled. This is so because, for instance, a voluminous newspaper cannot be produced during a single pass through the rotary printing press, rather as a general rule there are required a number of production steps which are staggered in time, and in the last production step there is formed the topical section of the printer product (the so-called main product and in the case of newspapers the outermost section bearing usually the most newsworthy items) which then is combined, typically by carrying out a stuffing operation, with the previously formed sections (the so-called pre-products or intermediate sections in the case of a newspaper) into the actual newspaper copy.
However, the developments which have occurred in this particular field of technology up to the present time have not gotten away from the formation of the conventional, approximately quadratic-shaped stack. This factor combined with the increasing output capacity of rotary printing presses has resulted in the fact that a single one of the classical stackers, notwithstanding the measures undertaken to increase the efficiency or output thereof and associated with considerable technological expenditure (for instance shortening the ejection times of the finished formed stacks and increasing the stack height, possibly, with the aid of a cartridge-like truss or the like), is hardly capable of stacking in a disturbance free manner the entire output of a rotary printing press.
Apart from the foregoing there is an additional factor which must be considered, to wit: the printed products stacked into conventional quadratic-shaped stacks (with or without the aid of stack cartridges) oftentimes require a further handling (e.g. insertion of the pre-product into the main product), so that as a rule the stack again must be transformed into a fish scale stream or overlapping arrangement. However, such practically cannot be carried out without previously separating the stack, and for this purpose there are required technically complicated devices, such as for instance feeding apparatus.